This application deals with a proposed collaboration between one of the laboratories at the Center for Molecular Genetics and the Department of Biology at the University of California, San Diego, and one of the laboratories at the Center for Cellular and Molecular Biology at Hyderabad, India. The proposed experiments which will be carried out primarily at the Center for Cellular and Molecular Biology, deal with the relationship between transcription and chromatin-packaged DNA. The specific emphasis of the research is on the RNA polymerase III of yeast (Saccharomyces cerevisiae) transcribing the yeast gene that encodes an RNA (the so-called U6 small nuclear RNA) of the yeast splicing apparatus. Specifically, the aims of this FIRCA will be to explore: 1) The status of nucleosome positioning in and surrounding the yeast U6 gene after binding of the RNA polymerase III transcription initiation factor TFIIIC and formation of a pre-initiation complex. 2) Whether the chromatin-remodeling activity of Drosophila embryo extract (designated S-190), which is known to affect transcription of various RNA polymerase II genes, also makes this RNA polymerase III gene active for transcription. If it is active, then the objective of the research will to determine whether that activity is ATP-hydrolysis- dependent and whether it is directed by the yeast transcription factor TFIIIC. 3) Whether the yeast TFIIIC factor possesses an intrinsic chromatin- remodeling activity. The proposed research deals with basic mechanisms that determine gene activity. It is generally appreciated that understanding gene regulation is fundamental to devising new ways of combating infections and mutation- cased disease. Common elements of transcription mechanisms are shared by all organisms and all types of cells, because all transcription machineries share common evolutionary roots. In eukaryotic transcription, the relationship of nuclear polymerases I, II and III is especially close. For this reason, the proposed analysis of the well- defined and active yeast RNA polymerase III transcription system is clearly relevant to eukaryotic transcription.